Laser pointer

ABSTRACT

A laser pointer for continuously drawing arbitrary shapes on a surface comprises a micro-electro-mechanical system (MEMS) mirror configured to deflect an emitted laser beam, wherein the deflection angle of the MEMS mirror can be altered by means of applying a set of drive values to the MEMS mirror; an orientation measurement unit configured to continuously determine a current orientation and to output said current orientation at an output; a memory being configured to store current orientations received from the orientation measurement unit as a set of orientation samples; and a drive circuit configured to generate said set of drive values by subtracting the current orientation from the set of orientation samples and to apply said set of drive values to the MEMS mirror.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority to European PatentApplication Serial No. 18154213.5, filed on Jan. 30, 2018, which isherein incorporated by reference in its entirety.

FIELD OF INVENTION

The present subject matter relates to a laser pointer for drawingarbitrary shapes on a surface, e.g., a wall, board, or the like.

BACKGROUND OF THE INVENTION

During the last three decades, laser pointers became a necessity forpresentations in business meetings, school events, and even publicspeeches. Laser pointers make it easy to highlight areas on presentationmaterial that is usually hard to reach for the presenter by projecting alight spot in various colors—ranging from blue to green and red. Theselittle light generators help to temporarily mark an area on a slide orposter, for which the presenter only has to move the projected lightspot to an area of interest.

However, many presenters often find themselves in a pickle when theywant to highlight an entire word because underlining a many charactersis only possible by frantically waving your laser pointer, causingdistraction to the audience and frustration for the presenter.Furthermore, adding words or drawings to slides or posters is notpossible at all, and presenters have to resort to ancient technologiessuch as markers, highlighters or even adding paper scraps with adhesivetape to the presentation material on the wall.

In other areas, laser pointers have made technological advances. Forexample, US 2007/0023527 A1 describes a laser pointer that reduces handtremors of a nervous presenter by counteracting the laser pointer'smovement on a low scale. To this end, this laser pointer is equippedwith an orientation sensor and a mirror system to invert the movement ofthe laser pointer, resulting in a more or less static laser spot on thewall. Additionally, this laser pointer can project predetermined shapessuch as lines or circles by linearly driving the MEMS(micro-electro-mechanical systems) mirror.

Unfortunately, these predetermined shapes do not allow the presenter toexpress his or her thoughts or artistic freedom as he or she isrestricted to lines and circles. While it would be straightforward topre-program this laser pointer for additional shapes such as rectanglesor even star shapes, the presenter would still be severely restricted tothe options of the laser pointer.

SUMMARY

It is therefore an object of the disclosed subject matter to provide animproved laser pointer that overcomes the problems of the state of theart.

To this end, the disclosed subject matter provides a laser pointer ofthe aforementioned type, comprising:

a laser generation unit configured to emit a laser beam;

a micro-electro-mechanical system (MEMS) mirror configured to deflectthe emitted laser beam, wherein the deflection angle of the MEMS mirrorcan be altered by means of applying a set of drive values to an input ofthe MEMS mirror;

an orientation measurement unit configured to continuously determine acurrent orientation of the laser pointer and to output said currentorientation at an output;

a memory having an input that is connected to the output of theorientation measurement unit, the memory being configured to storecurrent orientations received from the orientation measurement unit as aset of orientation samples;

a drive circuit having a first input connected to the memory forretrieving said set of orientation samples from the memory and a secondinput connected to the output of the orientation measurement unit forreceiving the current orientation from the orientation measurement unit;

wherein the drive circuit is configured to generate said set of drivevalues by subtracting the current orientation from the set oforientation samples and to apply said set of drive values to the inputof the MEMS mirror; and

wherein the memory is configured to continuously store new orientationsamples while the MEMS mirror is driven by the drive circuit, and thedrive circuit is configured to update the set of drive values when a neworientation sample is stored in the memory.

Such a laser pointer provides an exhilarating experience for presentersas they now can draw and even write on their presentation material inreal-time. By a simple wave of the hand, it is possible to project anarbitrarily curved line of light on a surface, e.g., a wall, board, orthe like. This allows presenters to modify slides and write-ups in frontof a live audience and also to delete the drawn shapes at will.

By using MEMS mirrors, previously marked areas on the wall, board, orthe like can be “re-visited” by the light spot without the need for thepresenter to actually move his or her hand. The drawn shape is memorizedwithin the laser pointer and played back with the MEMS mirror, evenduring the process of drawing. This gives the presenter a completely newand previously unheard-of feeling of using his/her presentation materialas he/she can develop the content of the slides on the fly.

To draw shapes that are bright on the wall and do not flicker, the samedrive values may be applied multiple times to the MEMS mirror such thatthe MEMS mirror “re-draws” the same shape multiple times. If this isdone in quick succession, the human eye cannot distinguish between theindividual cycles of the MEMS mirror and a static shape is experienced.For this purpose, the drive circuit is optionally configured torepeatedly apply the set of drive values to the MEMS mirror.

To ensure that the MEMS mirror is capable of displaying all of thegenerated drive values, although this may not be necessary if some drivevalues can be disregarded, in a further embodiment the rate of applyingthe individual drive values of the set of drive values to the MEMSmirror is at least N times higher than the rate of storing theindividual orientation samples in the memory, wherein N corresponds tothe number of orientation samples stored in the memory.

A challenge in practically realizing the laser pointer of theaforementioned type may be the usage of power. The longer and larger thedrawn shape becomes, the less bright it will be on the wall as the MEMSmirror takes a longer time to reproduce the shape. Thereby, also theamount of MEMS mirror cycles per time unit is reduced, resulting in adim output of the laser pointer. To overcome this, the disclosed subjectmatter provides several variants.

Firstly, the memory can be configured to delete an orientation samplefrom the memory after a predetermined time. By this means, the drawing“vanishes” after some time, making it temporary and freeing up memoryspace.

Secondly, the memory can be configured to delete the oldest orientationsample if a new orientation sample is stored. In this variant, thememory can have a maximum amount of storage such that also the amount ofdrive values to be generated is restricted. This is especially favorableif the presenter scribbles on the wall, board, or the like, as the laserpointer cannot suffer from an information overload, which would benear-impossible to reproduce with the MEMS mirror.

To further enhance the consistency of the intensity of the output andthus the quality of the drawn shape, the drive circuit optionally has afurther output connected to a control input of the laser generation unitand is further configured to control an intensity of the emitted laserbeam via said control input. Thereby, the drive circuit can adjust theintensity of the emitted laser beam to be proportional to the amount ofdrive values generated, i.e., increase the intensity if the drawn linebecomes longer. For this purpose, the intensity of the laser pointer canbe reduced in the beginning, e.g., to a value of 5%, 10%, 25%, or 50% ofits maximum output capability.

This embodiment can also be used to provide “gaps” in the drawn shape,for example to provide a spacing when letters are written. The drivecircuit can then specify that the intensity of the emitted laser beam iszero between specified drive values.

Sometimes it is also necessary for the presenter temporarily pause thedrawing mode to focus on other parts of his or her presentation or tosimply use the ordinary mode of projecting a single spot. Thus the laserpointer may optionally have an input device via which the storing ofcurrent orientations in the memory can be switched on and off.

The orientation sensor allows the laser pointer to record the changes inorientation, i.e., angular position, which are caused by the presentertilting his or her hand holding the laser pointer. This embodiment issufficient in most cases, as most of the movement of the laser pointeris caused by tilting the hand.

On the other hand, some presenters enjoy running from side to side withthe laser pointer in front of the wall, board or the like. This causesalso the written or drawn shape on the presentation material to movealong with the presenter. In a further embodiment, the laser pointer maythus compensate its translatory movement. To this end, the orientationmeasurement unit is further configured to continuously determine acurrent position of the laser pointer, wherein the memory is furtherconfigured to store current positions received from the orientationmeasurement unit together with the current orientations as a set oforientation samples with position samples, and wherein the drive circuitis configured to generate said set of drive values based on the currentorientation, the current position, and the set of orientation sampleswith position samples.

In most cases, the presenter is located at a constant distance in frontof the wall, board, or the like, even if he or she moves from side toside. If the presenter also moves to and from his/her presentationmaterial, this can cause a scaling problem for the projected shape. Toovercome this scaling problem, which also affects to a lesser degree theaforementioned compensation of the translatory movement, the laserpointer optionally comprises a distance measurement unit configured todetermine a current distance of the laser pointer from the surface, andto output said current distance at an output connected to an input ofthe memory and to an input of the drive circuit, wherein the memory isfurther configured to store current distances received from the distancemeasurement unit together with the current orientations and currentpositions as a set of orientation samples with position samples anddistance samples, and wherein the drive circuit is configured togenerate said set of drive values based on the current orientation, thecurrent position, the current distance, and the set of orientationsamples with position samples and distance samples.

Optionally, the laser pointer further comprises a sampler interposedbetween the orientation measurement unit and the memory, wherein thesampler is configured to output orientation samples at a constant rateto the memory for storing. This can be used to store currentorientations at regular intervals and/or only when the change of currentorientations exceeds a predetermined threshold, effectively reducingrequired memory size and the computational steps the drive circuit hasto perform.

Further optionally, the laser pointer comprises a low-pass filterinterposed between the orientation measurement unit and the memory. Thisserves to remove hand-tremor jitters from the drawn shape such that,e.g., lines can be drawn straighter. Optionally, such a low-pass filtermay only be interposed between the orientation measurement unit and thememory and not between the orientation measurement unit and the drivecircuit because the drive circuit needs the deviations even of smallhand movements to compensate for hand tremors, such that the drawn shapecan be hold still on the wall.

Further optionally, the laser pointer has at least two laser generationunits, each configured for emitting a laser beam of a differentwavelength onto said MEMS mirror. The user can thus chose the color ofprojecting the light, for example by means of a manual switch.

In this embodiment the drive circuit may optionally be configured tocontrol the intensity of the laser beams emitted by the at least twolaser generation units and to use each of the laser generation units fordifferent subsets of the set of orientation samples. By means of this,the drive circuit can assign a certain color to a selected memory subsetand a different color to a different—or overlapping, to mixcolors—subset. For example, if the laser pointer is used for writing,one letter can be written in red and a different letter can be writtenin green.

Further optionally, the laser pointer has at least two MEMS mirrors,each configured for deflecting at least a part of said laser beam,wherein the drive circuit is configured to generate said set of drivevalues for each of the MEMS mirrors. This can be done either by means ofarranging two MEMS mirrors in a serial manner or—for example with theuse of a beam splitter—in a parallel manner. This can be used toovercome the limits in deflection angle of MEMS mirrors, which istypically max. 60°-120° when optically extending the optical scan angle.If two MEMS mirrors are used in parallel, one mirror could be used toproject shapes on the far left and the other to project shapes on thefar right; if two MEMS mirrors are used serially, the second onemultiplies the deflection angle of the first.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosed subject matter shall now be explained in more detail belowon the basis of exemplary embodiments thereof with reference to theaccompanying drawings, in which:

FIG. 1a shows a laser pointer according to the disclosed subject matterin the process of drawing a shape on a wall of a room in a perspectiveview;

FIG. 1b shows the laser pointer of FIG. 1a after completing the drawingof the shape in a perspective view;

FIG. 2 shows the components of a first embodiment of the laser pointerof FIGS. 1a and 1b in a schematic circuit diagram; and

FIG. 3 shows the components of a second embodiment of the laser pointerof FIGS. 1a and 1b in a schematic circuit diagram.

DETAILED DESCRIPTION

FIG. 1a shows a laser pointer 1 in a first position 2 emitting a laserbeam 3 onto a wall 4. Instead of a wall 4, the laser pointer 1 couldalso emit the laser beam 3 onto any kind of surface, such as a board,projection screen, poster, a slide projected by an external projector,or the like.

The laser pointer 1 is used to draw an arbitrary shape 5, in the case ofFIG. 1a a curved line, onto the wall 4 by tilting the laser pointer 1from a first orientation θ₀ in the first position 2 to a secondorientation θ_(i) in a second position 6 with a tilting movement 7,e.g., by tilting the hand holding the laser pointer 1. In the secondposition 6, a state-of-the-art laser pointer would naturally only emitone laser beam 8 to project one spot onto the wall 4. The laser pointer1, however, is capable of deflecting the laser beam 8 along a movementthat corresponds to the tilting movement 7 previously performed by thelaser pointer 1 to “re-draw” the shape 5 onto the wall in the secondposition 6. This is done by emitting a fan of laser beams 8 in such amanner that not only the present orientation θ_(i) but all previousorientations θ_(i-1), θ_(i-2), . . . , θ₀ that were assumed by the laserpointer 1 between the first position 2 and the second position 6 areincluded in the fan of laser beams 8.

FIG. 1b shows that the laser pointer 1 moved even further from the firstposition 2 over the second position 6 to a third exemplary position 9with a tilting movement 10 of the user's hand. Also in FIG. 1 b, thelaser pointer 1 emits a fan of laser beams 12 in such a manner that notonly the present orientation θ_(i) but all previous orientationsθ_(i-1), θ_(i-2), . . . , θ₀ that were assumed by the laser pointer 1between the first position 2, the second position 6, and the thirdposition 9 are included in the fan of laser beams 12.

It can be seen from FIG. 1b that while in the second position 6 thelaser pointer 1 already re-drew the beginning of the shape 5, thecomplete shape 5 is now re-drawn in the third position 9. This allowsthe user to draw any arbitrary shape 5 in real-time, just like with penon paper usage. It is not necessary for a user to first define the shape5 to be projected by the tilting movement 10 and only then start thecomposed projection, as this would make drawing more complex shapes suchas letters and/or drawing shapes precisely at certain target positionson a wall very hard.

FIG. 2 shows the components of the laser pointer 1 that allow thereal-time drawing of shapes 5 as described above with reference to FIGS.1a and 1 b. The laser pointer 1 comprises a laser generation unit 13that emits the laser beam 3, 8, 12. The laser generation unit 13 can beof any type known in the state of the art, for example a laser diode, adiode-pumped solid-state frequency-doubled laser, a light-emittingdiode, or a superluminescent light-emitting diode. The laser beam 3, 8,12 can be of any wavelength to produce any desired color.

The laser beam 3, 8, 12 is emitted onto a MEMS (micro-electro-mechanicalsystem) mirror 14 comprising a motor component 15 and a mirror component16. The motor component 15 and the mirror component 16 are commonlyembodied in a single element as known in the state of the art.

The deflection angle Φ of the MEMS mirror 14 can be electromechanicallyaltered by applying a set of drive values DV to an input 17 of the MEMSmirror 14. By altering the deflection angle γ, the laser beam 3, 8, 12can be dynamically deflected to produce the fan of laser beams 8, 12shown in FIGS. 1a and 1 b. Generally, the MEMS mirror can be rotatedabout two axes to allow a deflection of the laser beam 3, 8, 12 on atwo-dimensional area, i.e., the deflection angle Φ is an angle in space.

To determine the current orientation θ_(i) of the laser pointer 1, anorientation measurement unit 18 is used. The orientation measurementunit 18 is fixated in a casing 11 of the laser pointer 1 which housesthe components shown in FIG. 2. The orientation measurement unit 18 iscapable of determining angular movements of the laser pointer 1 and canfor this purpose be an IMU (inertial measurement unit), one or moregyroscopes, one or more magnetometers, a camera viewing and processingthe environment of the laser pointer 1, or the like.

The orientation measurement unit 18 can determine the currentorientation θ_(i) of the laser pointer 1 in an absolute or relativemanner. For an absolute determination of the orientation θ_(i) in space,for example a set of two angles α, β around reference axes can be used,see FIG. 1 a. To determine a relative orientation θ_(i), it is onlynecessary to define a reference orientation, for example the orientationθ₀ in the first position 2 (FIG. 1a ), and determine all followingorientations θ_(i) with respect to this reference orientation θ₀.

To record the laser pointer's movement 7, 10 from one position to thenext, a sequence of current orientations θ_(i) is stored in a memory 19.To this end, an output 20 of the orientation measurement unit 18 isconnected to an input 21 of the memory 19. The memory 19 can be of anytype known in the state of the art, for example embodied as a digitaldatabase on a data storage, as a shift register, or as a circularbuffer.

The memory 19 stores the current orientations θ_(i) output by theorientation measurement unit 18 as a set S of orientation samples 22.While the current orientations θ_(i) can be output in any form, eitheras discrete values output at regular or irregular times or even as ananalog signal, the set S of orientation samples 22 is a set of discretevalues. In the simplest case a sequence of past discrete currentorientations θ_(i) is the same as the set S of orientation samples 22.

In the embodiment of FIG. 2, an optional sampler 23 is interposedbetween the orientation measurement unit 18 and the memory 19 totransform the current orientations θ_(i) into the set S of orientationsamples 22. The sampler 23 outputs the orientation samples 22 at aconstant rate to the memory 19 for storing such that the memory 19 hasno further need of processing the current orientations θ_(i).

Depending on the method to generate the set S of orientation samples 22,the orientation samples 22 can either have a fixed span of time betweentheir respective times of recording, e.g., each orientation sample 22 isrecorded 1 ms after the preceding orientation sample 22, or theorientation samples 22 can have a fixed angular difference with respectto each other, e.g., each orientation sample 22 is recorded 0.01° afterthe preceding orientation sample 22. Other criteria are possible, too.

Furthermore, a low-pass filter 24 can optionally be interposed betweenthe orientation measurement unit 18 and the memory 19. The low-passfilter 24 can be used to eliminate jitter from recorded lines such thatonly straight lines or smooth movements are recorded.

To generate the drive values DV for driving the MEMS mirror 14, a drivecircuit 25 is used. The drive circuit 25 has a first and a second input26, 27. Via the first input 26, the drive circuit 25 is capable ofretrieving the con-tents of the memory 19. Depending on the type ofmemory 19 used, the drive circuit 25 can either read out the whole set Sof orientation samples 22 at once, for example by a data transfer of adigital list, or sequentially retrieve the orientation samples 22(θ_(i), θ_(i-1), θ_(i-2), . . . ) until the last orientation sample θ₀is reached, whereupon the drive circuit 25 re-starts the step ofretrieving at the first orientation sample θ_(i) as is indicated byarrow 28. Via the second input 27 the drive circuit 15 receives,directly from the orientation measurement unit 18, the currentorientation θ_(i).

For generating the drive values DV, the drive circuit 25 comprises asubtractor 29, which generates a set of drive values DV by subtractingthe current orientation θ_(i) from each orientation sample 22 retrievedfrom the memory 19. It is to be understood that the term “subtractor” isonly used for purposes of visualization as the subtractor 29 can assumea lot of other functions such as converting the result of thesubtraction into a corresponding voltage for driving the MEMS mirror,applying scaling functions, or the like. Once the set of drive values DVis generated, it is applied—as a sequence of individual drive values DVeach corresponding to one orientation sample 22 minus the currentorientation θ_(i)—to the input 17 of the MEMS mirror 14 via an output 30of the drive circuit 25.

It is further to be understood that all the aforementioned steps ofdetermining and storing current orientations θ_(i), emitting the laserbeam 3, 8, 12, and driving the MEMS mirror 15 are performedsimultaneously to allow a real-time drawing of the shape 5 on the wall 4as shown in FIGS. 1a and 1 b. For this reason it is especially providedthat the memory 19 is configured to continuously store new orientationsamples 22 while the MEMS mirror 14 is driven by the drive circuit 25,and the drive circuit 25 updates the set of drive values DV at leastwhen a new orientation sample 22 is stored in the memory 19.

The drive circuit 25 can comprise additional functions such as a patternrecognition algorithm that can determine if the user wants to draw acircle or a line. In this case, the drive values DV are manipulated suchthat instead of a crooked circle or a wiggly line a perfectly roundcircle or a straight line is output. The same can be utilized forletters, which is especially advantageous as writing with a laserpointer can be challenging for a presenter. To this end, even differenttypesets could be chosen such that the user's handwriting can bedisplayed in “Courier” or “Arial” typeset, for example.

Furthermore, the drive circuit 25 can “re-arrange” the drive values DVwithin the set of drive values DV to determine the fastest way for theMEMS mirror 14 to reproduce the contents of the memory 19, i.e., theMEMS mirror 14 does not have to reproduce the movement 7, 10 in achronological manner but alternatively can do this in a more efficientway. This is especially useful if the movement 7, 10 contains multipledisconnected shapes such as letters.

When the drive circuit 25 outputs the set of drive values DV to the MEMSmirror 14, it does so repeatedly such that the MEMS mirror 14 projectsthe fan of laser beams 8, 12 multiple times. For example, the same setof drive values DV can be repeatedly output to the MEMS mirror 14 aslong as the content of the memory 19 or the current orientation θ_(i)does not change.

Furthermore, the computation of the subtraction by means of thesubtractor 29 can be performed continuously even with changing currentorientations θ_(i). For example, from a first part of the set S oforientation samples 22 a current orientation θ_(i) is subtracted andfrom a second part of the set S of orientation samples 22 a differentcurrent orientation θ_(i) is subtracted if a change in currentorientation θ_(i) occurred in the middle of retrieving the set S.

In most embodiments, the rate of applying the individual drive values DVof the set of drive values DV to the MEMS mirror 14 is at least N timeshigher than the rate of storing the individual orientation samples 22 ofthe set S in the memory 19, wherein N corresponds to the number oforientation samples 22 stored in the memory 19, i.e., the size of theset S.

It can be seen that a cycle of outputting a set of drive values DV bythe MEMS mirror 14 takes longer if there are a lot of drive values DV inthe set of drive values DV. As such, the rate of outputting sets ofdrive values DV decreases if long shapes 5 are drawn. Thereby, also theintensity of the shape 5 as displayed on the wall 4 reduces. As apractical example, while a short shape 5 can be repeated 1000 times persecond, a large shape 5 with 10 times the length of the short shape 5can only be repeated 100 times per second, meaning also the intensity is10 times lower for the long shape 5. Various measures can be taken tosolve this issue.

Firstly, the memory 19 can delete each orientation sample 22 from thememory 19 after a predetermined time, for example after 10 seconds. Thisreduces the amount of orientation samples 22 in the memory 19 and thusalso the amount of drive values DV in the set of drive values DV.

Secondly, the memory 19 can delete the oldest orientation sample 22 fromthe memory 19 if a new orientation sample 22 is stored. The set S oforientation samples 22 can thus be restricted to a predefined size, forexample N=1000 orientation samples 22. If the 1001-st orientation sample22 is to be stored, the oldest of the 1000 previously stored orientationsamples 22 is deleted. This also limits the amount of orientationsamples 22 in the memory 19 and thus the amount of drive values DV inthe set of drive values DV.

In addition to these two measures, the drive circuit 25 can have afurther output 31 connected to a control input 32 of the lasergeneration unit 13 and via this connection control the intensity P ofthe emitted laser beam 3, 8, 12. For example, the drive circuit 25 cancontrol the intensity P of the emitted laser beam 3, 8, 12 such that theintensity P of the emitted laser beam 3, 8, 12 is proportional to thenumber of drive values DV in said set of drive values DV. In this way,the drive circuit 25 can reduce the intensity P of the laser beams 3, 8,12 emitted by the laser generation unit 13 when driving the MEMS mirror14 for short shapes 5 and only use the full intensity P for the laserbeams 3, 8, 12 when driving the MEMS mirror 14 for long shapes 5.

To allow the user to draw a multitude of independent shapes 5, the laserpointer 1 has an input device 33 via which the storing of currentorientations θ_(i) in the memory 19 can be switched on and off. Theinput device can for this purpose be a simple button or a touchpad.

FIG. 3 shows a variant of the laser pointer of FIG. 2, in which theorientation measurement unit 18 can additionally continuously determinea translatory shift, i.e., a current position p_(i). For this purpose,common IMUs, accelerometers, magnetometers, or dead-reckoning systemscan be used, or cameras recording and processing the environment.Alternatively or additionally, GPS coordinates could be used fordetermining the current position. Also, the laser pointer 1 could beconnected with a nearby provider of reference signals, for example amobile phone, which can act as a beacon and thus be used to determinethe relative distance of the laser pointer 1 to the mobile phone.

Current positions p_(i) are received by the memory 19 from theorientation measurement unit 18 and stored together with the currentorientations θ_(i) as a set S′ of orientation samples 22 with positionsamples 34. The aforementioned sampler 23 and low-pass filter 24 can beutilized for the current positions p_(i), too.

To compute the drive values DV, the drive circuit 25 receives inaddition to the current orientation θ_(i) also the current positionp_(i). The computation of the drive values DV can in this case not beperformed with a subtraction, but is still simple enough to bedetermined by utilizing the principles of basic geometry.

Furthermore, the laser pointer 1 can also autonomously determine itsdistance d_(i) to the wall 4 by measuring the time-of-flight betweenemitting the beam 3, 8, 12 and receiving the reflection 35 of the laserbeam 3, 8, 12 from the wall 4 in a distance measurement unit 36 of thelaser generation unit 13. Such systems are commonly known as LIDAR(light detection and ranging) systems.

Depending on the embodiment, the laser generation unit 13 and thedistance measurement unit 36 can be two distinct but connectedcomponents that can interact with each other, e.g., the laser generationunit 13 can communicate a time of generating the laser beam 3, 8, 12 tothe distance measurement unit 36 such that the distance measurement unit36 can determine a time of flight of the laser beam 3, 8, 12 afterreceiving the corresponding reflection. The laser generation unit 13 andthe distance measurement unit 36 could also be embodied as a singleunit.

The distance measurement unit 36 outputs the current distance d_(i) atan output 37 thereof to an input 38 of the memory 19. The memory 19 thenstores the current distances d_(i) received from the distancemeasurement unit 36 together with the current orientations θ_(i) andcurrent positions p_(i) as a set S″ of orientation samples 22 withposition samples 34 and distance samples 39.

The drive circuit 25 also receives the current distances di at an input40 and generates the set of drive values DV based on the currentorientation θ_(i), the current position p_(i), the current distanced_(i), and the set of orientation samples 22 with position samples 34and distance samples 39, again by means of applying basic geometry.

The laser pointer 1 can also comprise extended functions by employingmultiple laser generation units 13 and/or multiple MEMS mirrors 14. Inone embodiment (not shown), the laser pointer 1 has at least two lasergeneration units 13, each emitting a laser beam 3, 8, 12 of a differentwave-length onto said MEMS mirror 14. The user can then, for example,manually choose to display the shapes 5 in green, blue, orange, red, orany other desired color provided by the multiple laser generation units13. A mixing of colors is possible, too.

It is even possible to vary the color within the same shape 5 (or fordifferent shapes, e.g., different letters). To this end, the drivecircuit 25 can control the intensity P of the laser beams 3, 8, 12emitted by at least two laser generation units 13 and to use each of themultiple laser generation units 13 for different subsets of the set ofdrive values DV.

The field of view of a MEMS mirror is typically 60°-120° when opticallyextending the optical scan angle. While this is enough for someapplications, the MEMS mirror 14 can generally deflect the laser beam 3,8, 12 over a wider spatial area. To this end, the laser pointer 1 canhave at least two MEMS mirrors 14, each deflecting at least a part ofsaid laser beam 3, 8, 12, and the drive circuit 25 splits the set ofdrive values DV into partial sets for each of the MEMS mirrors 14. Forexample, a beam splitter can be used to provide a part of the laser beam3, 8, 12 for each MEMS mirror. The MEMS mirrors could alternatively alsobe cascaded to achieve a different or widespread behavior of deflection.

The disclosed subject matter is not restricted to the specificembodiments described in detail herein, but encompasses all variants,combinations and modifications thereof that fall within the framework ofthe appended claims.

1. (canceled)
 2. The laser pointer according to claim 25, wherein thedrive circuit is configured to repeatedly apply the set of drive valuesto the MEMS mirror.
 3. The laser pointer according to claim 25, whereinthe rate of applying the individual drive values of the set of drivevalues to the MEMS mirror is at least N times higher than the rate ofstoring the individual orientation samples in the memory, wherein Ncorresponds to the number of orientation samples stored in the memory.4. The laser pointer according to claim 25, wherein the memory isconfigured to delete an orientation sample from the memory after apredetermined time.
 5. The laser pointer according to claim 25, whereinthe memory is configured to delete the oldest orientation sample if anew orientation sample is stored.
 6. The laser pointer according toclaim 25, wherein the drive circuit has a further output connected to acontrol input of the laser generation unit and is further configured tocontrol an intensity of the emitted laser beam via said control input.7. The laser pointer according to claim 6, wherein the drive circuit isconfigured to control the intensity of the emitted laser beam such thatthe intensity of the emitted laser beam is proportional to the number ofdrive values in said set of drive values.
 8. The laser pointer accordingto claim 25, wherein the laser pointer has an input device via which thestoring of current orientations in the memory can be switched on andoff.
 9. The laser pointer according to claim 25, wherein the orientationmeasurement unit is further configured to continuously determine acurrent position of the laser pointer, wherein the memory is furtherconfigured to store current positions received from the orientationmeasurement unit together with the current orientations as a set oforientation samples with position samples, and wherein the drive circuitis configured to generate said set of drive values based on the currentorientation, the current position, and the set of orientation sampleswith position samples.
 10. The laser pointer according to claim 9,wherein the laser pointer further comprises a distance measurement unitconfigured to determine a current distance of the laser pointer from thesurface, and to output said current distance at an output connected toan input of the memory and to an input of the drive circuit, wherein thememory is further configured to store current distances received fromthe distance measurement unit together with the current orientations andcurrent positions as a set of orientation samples with position samplesand distance samples, and wherein the drive circuit is configured togenerate said set of drive values based on the current orientation, thecurrent position, the current distance, and the set of orientationsamples with position samples and distance samples.
 11. The laserpointer according to claim 25, wherein the laser pointer furthercomprises a sampler interposed between the orientation measurement unitand the memory, wherein the sampler is configured to output orientationsamples at a constant rate to the memory for storing.
 12. The laserpointer according to claim 25, wherein the laser pointer furthercomprises a low-pass filter interposed between the orientationmeasurement unit and the memory.
 13. The laser pointer according toclaim 25, wherein the laser pointer has at least two laser generationunits, each configured for emitting a laser beam of a differentwavelength onto said MEMS mirror.
 14. The laser pointer according toclaim 13, wherein the drive circuit is configured to control theintensity of the laser beams emitted by the at least two lasergeneration units and to use each of the laser generation units fordifferent subsets of the set of orientation samples.
 15. The laserpointer according to claim 25, wherein the laser pointer has at leasttwo MEMS mirrors, each configured for deflecting at least a part of saidlaser beam, wherein the drive circuit is configured to generate said setof drive values for each of the MEMS mirrors.
 16. The laser pointeraccording to claim 9, wherein the drive circuit is configured torepeatedly apply the set of drive values to the MEMS mirror.
 17. Thelaser pointer according to claim 9, wherein the memory is configured todelete an orientation sample from the memory after a predetermined time.18. The laser pointer according to claim 9, wherein the memory isconfigured to delete the oldest orientation sample if a new orientationsample is stored.
 19. The laser pointer according to claim 9, whereinthe drive circuit has a further output connected to a control input ofthe laser generation unit and is further configured to control anintensity of the emitted laser beam via said control input.
 20. Thelaser pointer according to claim 9, wherein the laser pointer furthercomprises a low-pass filter interposed between the orientationmeasurement unit and the memory.
 21. The laser pointer according toclaim 25, wherein the orientation measurement unit comprises a cameraconfigured to view and process an environment of the laser pointer. 22.A laser pointer comprising: a laser generation unit configured to emit alaser beam; a micro-electro-mechanical system (MEMS) mirror configuredto deflect the emitted laser beam, wherein the deflection angle of theMEMS mirror can be altered by means of applying a set of drive values toan input of the MEMS mirror; an orientation measurement unit configuredto continuously determine a current orientation of the laser pointer andto output said current orientation at an output; a memory having aninput that is connected to the output of the orientation measurementunit, the memory being configured to store current orientations receivedfrom the orientation measurement unit as a set of orientation samples; adrive circuit having a first input connected to the memory forretrieving said set of orientation samples from the memory and a secondinput connected to the output of the orientation measurement unit forreceiving the current orientation from the orientation measurement unit;wherein the drive circuit is configured to generate said set of drivevalues by subtracting the current orientation from the set oforientation samples and to apply said set of drive values to the inputof the MEMS mirror; wherein the memory is configured to continuouslystore new orientation samples while the MEMS mirror is driven by thedrive circuit, and the drive circuit is configured to update the set ofdrive values when a new orientation sample is stored in the memory; andwherein the rate of applying the individual drive values of the set ofdrive values to the MEMS mirror is at least N times higher than the rateof storing the individual orientation samples in the memory, wherein Ncorresponds to the number of orientation samples stored in the memory.23. A laser pointer comprising: a laser generation unit configured toemit a laser beam; a micro-electro-mechanical system (MEMS) mirrorconfigured to deflect the emitted laser beam, wherein the deflectionangle of the MEMS mirror can be altered by means of applying a set ofdrive values to an input of the MEMS mirror; an orientation measurementunit configured to continuously determine a current orientation of thelaser pointer and to output said current orientation at an output; amemory having an input that is connected to the output of theorientation measurement unit, the memory being configured to storecurrent orientations received from the orientation measurement unit as aset of orientation samples; a drive circuit having a first inputconnected to the memory for retrieving said set of orientation samplesfrom the memory and a second input connected to the output of theorientation measurement unit for receiving the current orientation fromthe orientation measurement unit; wherein the drive circuit isconfigured to generate said set of drive values by subtracting thecurrent orientation from the set of orientation samples and to applysaid set of drive values to the input of the MEMS mirror; wherein thememory is configured to continuously store new orientation samples whilethe MEMS mirror is driven by the drive circuit, and the drive circuit isconfigured to update the set of drive values when a new orientationsample is stored in the memory; wherein the drive circuit has a furtheroutput connected to a control input of the laser generation unit and isfurther configured to control an intensity of the emitted laser beam viasaid control input such that the intensity of the emitted laser beam isproportional to the number of drive values in said set of drive values.24. A laser pointer comprising: a laser generation unit configured toemit a laser beam; a micro-electro-mechanical system (MEMS) mirrorconfigured to re-draw a shape onto a surface in at least a secondposition by deflecting the emitted laser beam along a movement thatcorresponds to a tilting movement previously performed by the laserpointer from at least a first position to the at least second position;wherein the tilting movement is memorized within the laser pointer forbeing re-drawn as said shape by the MEMS mirror.
 25. The laser pointeraccording to claim 24, wherein a deflection angle of the MEMS mirror canbe altered by means of applying a set of drive values to an input of theMEMS mirror; the laser pointer further comprising: an orientationmeasurement unit configured to continuously determine a currentorientation of the laser pointer and to output said current orientationat an output; a memory having an input that is connected to the outputof the orientation measurement unit, the memory being configured tostore current orientations received from the orientation measurementunit as a set of orientation samples; a drive circuit having a firstinput connected to the memory for retrieving said set of orientationsamples from the memory and a second input connected to the output ofthe orientation measurement unit for receiving the current orientationfrom the orientation measurement unit; wherein the drive circuit isconfigured to generate said set of drive values by subtracting thecurrent orientation from the set of orientation samples and to applysaid set of drive values to the input of the MEMS mirror; and whereinthe memory is configured to continuously store new orientation sampleswhile the MEMS mirror is driven by the drive circuit, and the drivecircuit is configured to update the set of drive values when a neworientation sample is stored in the memory.